Prism-telescope.



No. 674,465. Patented May 2|, |90l.

C. HENSOLDT.

PRISM TELESCOPE.

(Application lad Nov. 12, 1900.)

(No Indel.)

FIGLI.-

VIG-2.

UNITED STATES CARL HENSOLDT, OF

PATENT EEicE.

WETZLAR, GERMANY PRISM-TELESCOPE.

SPECIFICATION forming part of Letters Patent No. 674.465, dated May 21,1901i.

Application led November l2. 1900. Serial No. 36.229. (No model.)

To all whom t may concern:

Be it known that I, CARL HENSOLDT, a subject of the German Emperor,residing at 44 Steinweg, Wetzlar, Germany, have invented certain new anduseful Improvements in Prism-Telescopes, of which the following is aspecification.

This invention relates to improvements in prism-telescopes.

In the prisms extensively used in connection with prislntelescopes onetace or" a pentagen-al prism is beveled in the form of a saddle-roof,the said beveling producing a reversal oi' the object. A triangularprism is usually placed against or cemented to the pentagonal prism insuch a manner that one face of the triangular prism coincides exactlywith the adjacent face of the pentagonal prism. Vith the arrangementabove described-that is to say, with the prisms directly abuttingagainst each other or cemented togethers-rays entering at the edge ofthe pen'tagonal prism are so near to the triangular prism thatreflections appear at once if the observation does not take placeabsolutely in the line of the optical axis. Observations of this kindabsolutely in the line of the optical axis allow of only a smallundisturbed field of vision.

In the annexed drawings, Figure lis a diagrammatic view showing theimproved arrangement of the prisms, and Fig. 2 shows in partial sectiona binocular prism-telescope constructed according to this invention.

According to the present invention for the purpose of removing thedisadvantages above referred to the two prisms A and B are placed withregard to each other in the position represented in Fig. l-that is tosay, the adja-v cent -faces of the prisms do not coincide, but the edgesot' the triangular prism. are slightly raised above or out of line withthose of the pentagonal prism, the triangular prism B being thusdisplaced in a parallel and vertical sense with regard to the opticalaxis of the prism A. The entrance of the indirect disturbing reflectionsis thus prevented, as in dicated in said figure. The method oliemploying this combination is shown in Fig. 2.

To the tube a of the telescope are screwed in the known manner, by meansof screws d and c, the plates I) and c, holding, respectively,

the eye-lens and the object-glass. Directly to the inside of the frameor setting of the object-glass in the plate c a conical tubefis screwed.Two interconnected walls or supports g for the prisms are connected withthe said tubef by means ot' two opposite screws 7L in such a manner thatwhen the said scre ws 7i are unscrewed the said supports g can be turnedon their central axis for a certain distance, determined by the slots'Il The set of prisms is inserted between the supports g. In the examplerepresented in the annexed drawings the said set of prisms is composedof a combination ot' a pentagonal and a triangular prism. For thepurpose of holding the prisms a clamping device lt, screwed be tween thesupports `c/,is provided. The plates lm and m n of the said clampingdevice grip the corresponding faces of the pentagonal prism. For lateraldisplacement longitudinal slots o are provided in the supports g,through which the screws 1J, screwed into the clamping device it, arepassed. By unscrewing said screws p lateral displacement ot' the bodyot' prisms, and by unscrewing the screws h rotation of the set of prismson the axis, is permitted.

It the prism-telescope is used .in binocular form the frame can beprovided with suitable devices for adjusting the eye-lenses. In thisarrangement the outer casi ng of the telescope can be constructedseparately, as the adjustment of the prisms may take place independentlyand the eye-lenses and object-glasses can be directly connected with thecorresponding plates. In order, however, to permit the adjustment of theeye-lenses by rot-ation on a common axis and also the adjustment oftheir distance from the object-glasses by means of a mechanism similarto that of binoculars of ordinary construction, an arrangement is madeby which the operating mechanism is not situated in the center of theconnecting-joint between the two main parts, but below the same, betweena joint for the eye-lenses and the cross-pieces connecting the casingsof the prisms. The main joints q, r, and s rotate on a spindle t, uponwhich the two cross-pieces it for the eye-lens tubes e are arranged.This shaft t is provided with an external screw-thread 1U and engages arotatable hollow cylinder rc, pro- IOO vided with a Wheel y, so that onthe latter being-revolved the cylinder a: revolves and the axialmovement of the shaft t, carrying the eye-lenses, is rendered possibleby means of a pin z, rigidly connected with the said cylinder At thesame time the hinge-like rotation of the cross-pieces u, renders itpossible to advance or recede the ocular lenses. After accurateadjustment of the telescope it can be fixed by means of the screws s.

I declare that what I claim is- 1. In a telescope, the combination witha pentagonal and a triangular prism arranged so that the adjacent edgesof the latter are slightly raised or out of line with those of theformer by which vertical and parallel displacement the entrance ofindirectly-disturb= ing reflections is prevented, of a supporting Aandclamping device for said prisms and means for permitting.r axial andlateral adjustment of the prisms with regard to the lelescopesubstantially as described.

2. In a telescope, the combination with a pentagonal and a triangularprism arranged so that the adjacent edges of the latter are slightlyraised or out of line with those of the former by Which vertical andparallel displacement the entrance of indirectly-disturbing reflectionsis prevented, of a supporting,` and clamping device for said prismsconsisting of the supports g and plates Z fm and m n, adapted to gripthe pentagonalprism, and means provided with lthe slots z' and 0 andscrews h and p passing through said slots respectively for permittingaxial and lateral adjustment of the prisms with regard to the telescopesubstantially as described.

In witness whereof I have signed this specification in the presence oftwo Witnesses.

CARL HENSOLDT.

Witnesses:

JEAN GRUND, CARL GRUND.

